Difference in DBQL Tables V2R6 and V2R12(Demo).

Database
Enthusiast

Difference in DBQL Tables V2R6 and V2R12(Demo).

Hi All,

I have installed TD 12 Express Edition (Demo) on my system.
When i see the DBQL tables and Views under DBC. I can find two sets of both
having different names.

For Eg.

Tables:-
DBC.DBQLStepTbl
DBC.DBQLStepTbl_V2R6

Views:-
DBC.QryLogExplain
DBC.QryLogExplainV

And the query i fire is logged in both the tables and views inspite of different versions.

Please can anyone let me know the intention behind having this duplicacy ?

Is it something to do with the compability for different Teradata Versions.?

Thanks
Mtlrsk.

3 REPLIES
Teradata Employee

Re: Difference in DBQL Tables V2R6 and V2R12(Demo).

In TD12.0 and later, the data dictionary tables store character strings in Unicode. The "new" views with the "V" or "VX" suffix access the information without conversion; for backward compatibility, the "old" views now include translation from Unicode to Latin (or Kanji, if specified by the locale setting), and some fields are also CAST from VARCHAR to CHAR.

In your example, views DBC.QryLogExplain and DBC.QryLogExplainV both reference the same DBC.DBQLExplainTbl.

On the other hand, tables with version/release suffixes are created and used during "dictionary conversion" phase of an upgrade. Usually they are dropped by "post upgrade" cleanup procedures. I don't see DBC.DBQLStepTbl_V2R6 in my own Express Edition install (but there are a few empty tables with other release suffixes).
Enthusiast

Re: Difference in DBQL Tables V2R6 and V2R12(Demo).

Thanks Fred,

This has cleared most of the part.

Thank you very much for this prompt response.

Regards,

mtlrsk.
Enthusiast

Re: Difference in DBQL Tables V2R6 and V2R12(Demo).

Hi,
just want to correct 'v2r12' in the topic.
Version 1 has 5 major releases and Version 2 has 6 major releases, total 11.
The next release is called TD12, 'v2r12' is not a valid release name.

From Teradata 12 1098.pdf:
Release Numbering Changes
As of this release, Teradata is adopting one, unified numbering system for Teradata Database
and all of the associated tools and utilities. Teradata is making this change to reduce the
confusion caused by different release number sequences.
This release is called Teradata Database 12.0, and the collection of all the products, including
Teradata Database and Teradata Tools and Utilities, is called Teradata 12.0. This numbering
more accurately reflects the history of Teradata Database. There have been 11 prior major
releases (five major releases of Version 1 and six major releases of Version 2, including
V2R6.2).

Thanks,
-srinivas yelamanchili